Knee osteoarthritis (OA) is a common cause of pain and long-term disability in the elderly, and the incidence among middle-aged adults is considerable. Well-recognized risk factors associated with knee OA include age, women, being overweight or obese, major knee injury, and occupational overuse of the knee. Although loss of articular cartilage represents the pathological hallmark of knee OA, changes in subchondral bone and soft tissue are major features. Because knee OA is chronic and progressive, it is paramount that patients and health care professionals work together to manage symptoms, and to prevent and minimize deleterious consequences. Patient education, exercise, weight reduction, thermal modalities, assistive devices, medications, and neutraceuticals are important components of therapy. This article reviews common nonpharmacological and pharmacological therapies essential for the effective management of knee OA.